<!DOCTYPE html>
<meta charset="utf-8">
<title>Named access on the window object - changing attributes</title>
<link rel="author" title="Matthew Phillips" href="mailto:matthew@matthewphillips.info">
<link rel="help" href="https://html.spec.whatwg.org/#named-access-on-the-window-object">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<body>

<script>
"use strict";

test(() => {
  const img = document.createElement("img");
  document.body.appendChild(img);
  img.setAttribute("id", "changing-one");
  assert_equals(window["changing-one"], img);

  img.setAttribute("id", "changing-two");
  assert_false("changing-one" in window);
  assert_equals(window["changing-two"], img);
}, "Changing an attribute should update the named properties (id)");

test(() => {
  const img = document.createElement("img");
  document.body.appendChild(img);
  img.setAttribute("name", "changing-name-one");
  assert_equals(window["changing-name-one"], img);

  img.setAttribute("name", "changing-name-two");
  assert_false("changing-name-one" in window);
  assert_equals(window["changing-name-two"], img);

}, "Changing an attribute should update the named properties (name)");

test(() => {
  const img = document.createElement("img");
  document.body.appendChild(img);
  img.setAttribute("name", "still-match");
  img.setAttribute("id", "still-match");
  assert_equals(window["still-match"], img);

  img.setAttribute("id", "other");
  assert_equals(window["still-match"], img);
}, "Changing an attribute should not remove the named properties if a different attribute still matches (id)");

test(() => {
  const img = document.createElement("img");
  document.body.appendChild(img);
  img.setAttribute("name", "still-match-name");
  img.setAttribute("id", "still-match-name");
  assert_equals(window["still-match-name"], img);

  img.setAttribute("name", "other");
  assert_equals(window["still-match-name"], img);
}, "Changing an attribute should not remove the named properties if a different attribute still matches (name)");

test(() => {
  const img = document.createElement("img");
  img.setAttribute("alt", "Cat pictures on the internet");
  img.setAttribute("id", "no-errors");
  document.body.appendChild(img);
  assert_equals(window["no-errors"], img);

  img.setAttribute("alt", "Dog pictures on the internet");
  assert_equals(window["no-errors"], img);
}, "Changing an attribute that is not id or name should not cause errors");
</script>
</body>
